The present invention relates to a microlens array, a method for fabricating the same, and an optical device.
To date, a microlens array formed by arranging a plurality of minute lenses has been applied to a liquid crystal panel, for example. By applying the microlens array, the individual lenses focus incident light into corresponding pixels. Thus, a display screen can be made bright.
The lens side of the microlens array has bumps and dips, but it is required to be flat in order to form electrodes thereon. Conventionally, a flat surface has been formed by attaching a cover glass to the lens side with, for example, an adhesive and polishing it to make it thin. However, the polishing process in particular takes a long time.
The present invention aims to solve such problems. The object thereof is to provide a method for fabricating a microlens array having a flat surface by a simple process, the microlens array fabricated thereby, and an optical device.
(1) The method for fabricating the microlens array in the invention includes a first step of bringing a lens side of a microlens array substrate having a plurality of lenses formed thereon into close contact with a flat surface of a master plate, in which one surface is the flat surface, with a light transmitting layer precursor therebetween;
a second step of curing the light transmitting layer precursor to form a light transmitting layer; and
a third step of releasing the master plate from the light transmitting layer.
According to the invention, the light transmitting layer is formed on the lens side of the microlens array substrate. The upper side of the light transmitting layer is flattened by the flat surface of the master plate. In this manner, according to the invention, a simple process in which the master plate is brought into close contact with the light transmitting layer precursor and is then released can form the light transmitting layer having a flat surface on the lens side of the microlens array substrate.
(2) This method for fabricating the microlens array may further include a step of forming at least one of a black matrix, an electrode, and an alignment layer on the light transmitting layer.
According to this, at least one of the black matrix, the electrode, and the alignment layer can be formed on the flat surface of the light transmitting layer.
(3) This method for fabricating the microlens array may further include a step of depositing a protective coating on the light transmitting layer.
According to this, even though a material having a low durability is used as the light transmitting layer, the protective coating can protect the light transmitting layer.
(4) This method for fabricating the microlens array may further include a step of forming at least one of the black matrix, the electrode, and the alignment layer on the protective coat.
According to this, at least one of the black matrix, the electrode, and the alignment layer can be formed on the protective coating that has been deposited on the flat surface of the light transmitting layer.
(5) In the method described in any one of the methods for fabricating the microlens array, the light transmitting layer precursor may include a substance which can be cured by applying energy.
(6) In this method for fabricating the microlens array, the energy may be at least one of light and heat.
(7) In the method described in any one of the methods for fabricating the microlens array, the light transmitting layer precursor may be made of a resin.
(8) The microlens array in the invention is fabricated by the methods described above.
(9) The optical device in the invention has the microlens array described above.
(10) This optical device may be a display device having a light source for radiating light toward the microlens array.
(11) This optical device may be an imaging device having an image pick-up device that lights focussed by the microlens array enters.